Gas-compressor.



T SHIPLEY GAS COMPRESSOR.

APPLIOATION FILED nn.26,19o9.

Patented Aug. 10, 1909.

2 SHEETS-SHEET 1.

T. SHIPLEY. :GAS COMPRESSOR.

APPLIOATION FILED APB.. 26, 1909.

Patented Aug. 10, 1909.

2 SHEETS-SHEET 2.

L40 lvs allve controlled monts j's'.s-rlr-.Lirror Aroer,formNSYIMNte'.

ensroonrmrsso.

speeiecaftioaef Lsteratenej y @Patented "Aug-1o, 1909.

f annesse sleutel.. ma' .sesamo-.seelis- Qlogllvhom 'it Xorkzin she-.county iai York 1and ,State of ilonnsylyana, -haveginyentodgafnew $1aed-uso.-

55h11 lfm rovement in :Gas *Compressors of whieht efollowieg.isa-speeioation.

. My invention relates -to .,eornpressors --for ammonia ndthor gasesffer .usemorenars -`torllarlyin;refrigeratirrgplantswhoreinsulare 1.0 than one temperature is employed. In op.-

ierating these plantsit is necessary to reduce athenpressure at lwhiohrthe refrigerant oyapof ratesvwhen-a reduction.ofrtemperature isdesired. This makes .it `-rieoessary to Vhave -lmorerthanione pressure Where more :than one \ternperature,is-requiredier the work. -Underrny inyontion thedsiparate bodies of ses., each .at ,a pressure rent -frqin the other, .arerecelved and :taken foare vof in .one

2o .and :the same .compressor oylinjder @wherein -@they are .brought to :the .same :pressure 1 and '.migled, .and wherefromsthey are riallyiisf eharged :through a .common outlet- @his .1.

:om aware yis not broadly nevwfvitl1-L me.

lylyinventonresidos in oertain features. reiatlrllgizprinoipally.tothefrrlamer otintroduollgvtrising; their v,pressures .and mmglmg them-f .thefmain oharaeterlstc of the :improvement 'so being that the law v.pressure E.ses-. e1oter.s I.the

c linderion thefside .of lp1s ton opposite .tat. Qn which-tho fhigherzpressnre gas. enters y,that the 'l'opv pressure gas iillsthe cylinder .dpring-thedisohargestrokefofftho pistool-(tho I l.als .drsohar eautletgbeinaon the seme srerrith er pressure gas inlet) v.and thatfthis the hig low pressu'regas, by `and during .the return -orfsuotionstroke .of ,the piston, is .compressed .u ntil it forces its ,Way through one A or more Ipassages leading .mediately .orimmediately into thespaoe. on ,the other sigle of thge piston'vwihieh as' .entered by 'higher-pressure as duringthe suction stroke,

"l so thatgby the time the `suc/ tionfstroke is corn-I v f pletedJ-the cylinder is filled 'with gas at the Y, pressured the higherressure gas, rtlreswhole-of :the ,charge on the ow .pressure .ffmletsrale 'ofthe-piston having .-passedover .to .stheothersdo-thoreof .Aeomlprossor having mere genrrnogia age cunitnef power than any lotherdosgn `.of '.ooronrossor kno to me.

' .Then-.nature sof my .improyemont-ond the' infwxhioh :the same is orfmsyfbezeary.reel passas- {Elm-1.19pm

ivith the ,interior- .of

o gases-.111.110 the.oy-lillclo;r'andv of-LoquaL.

'the other `loon freorense .to :theaoeomeoying .drawing in .est knownthat l, .laomss 5mm-snai Figure -1 :is sramrnoto) .of somilohfof' .o -oomprossor y@y1- .inder and its piston and conneetions 1asis needediorthe p urpciseiof explanation; Fig.

.2 .is an .indioator .Gard .illustrativo of the aotion of the compressor. Fi s. 3 tand 4 are Jsectional views i s i111ilar.-to. ig. 1 of ymodiieatiQlls hereinafter more particularly referedtmh 1 de 1 .is te syl. .,r oastin Proper-herir .headsB-, Q,rarrdpiston llel, lower head .has astulng boxthrouglls -whioh the piston eadfhas in it a -anarsali-.sootion (largely die? .ot er ...bend :with .the .oyli'rrsor A' throughs Passage controlled @by y. .a5 inwardly @peeing lPerrot valve yc; ,and @it falso has :in .rita zdisshargo ohemberfGwrliiohsommuneates on tornei receiver in-rwhoh Athe .highly oom- .pressed vgas 1s stored Aand. en the. other hand e cylinder A -thrqugh a .passage 4controlled .by sn -outwardy opening i upEetvalyed It will lle-note' that the lso..- :inlet-.or sootion valvoeare .at tiresome en theoylinder. At thepther end offtheeylinfdor Anis .o nozzloforpossa .o :.Ewhoh oom- .mimioates on tho'on .with .the extro- :neous ,source (not .shovrn) from whieh the supplyof low, ressure gasis nlrawniand on `Withthe linterior of theeylini orge valve@ andtlio'highorpressuroo v the ooheiidwithitho oondonser or.y othereX- der A, ,this latter oomnlunicatiqn being con- -trolledby aninwordlyoponng puppetvolveb A s hereinb forev stated, Iprovlsjion should .-be made wherebyatcertaintirnes and under Aoertan Conditions communication may be .established medately .jor immediately between the ehambers inthe oylinderon -oppo- .site .sides of the piston.' I prefertoavail of the riston itself for this purpose. To this form in t one cir-.Amore passagesfr-.two in this instanef-through which direct, for immediate, .communication -may gbe .established-between thoohambors in the oylillolor 011 opposite .sides of piston, these Passages Aiboirlg soontrolled: bypirpnowolvoso @which .open onlyupward,or-.infrosponseto superior Ipressure from theilowgpressure inlet side of tho-piston.

It is assumed that the higher pressure gas enters at F at a ressure of 30 lbs. above atd mosphere (or Ilbs. absolute) ;v that the low pressure gas enters at E at a lbs. above atmosphere; and t at the compressed as -leaves the compressor through the disc arge G' at a pressure of 175 lbs. above atmosphere.

he operation under these conditions is as follows: When the piston on its u stroke has reached the upper cylinder head afterhaving discharged at d all the compressed gas, the cylinder space belowthe piston will be filled with gas at 15 lbs. pressure, drawn in through the suction nozzle E during the -rise of the piston. As soon as the piston. begins its down stroke, the suction valve c of cham.- ber F opens, th us allowing pressure to enter and fill the cylinder space above the piston. This gas being at 30 lbs. pressure, holds valves a a in the piston closed until bythedownward movement of the piston the gas belowthe latter has been compressed to a pressure above 30 lbs. As soon as this happens, the valves-a a will lift and ressure of 15 'allowthe gas to pass from below to above the y piston; and this gas vbeing at a higher pressure than' 30 lbs. will cause the suction valve c to close. Thereafter .during the down stroke of` the piston the gas pressure on both sides ofthe pistonpwill be equalized and consequently as the piston descends the gas will be merely dis laced from the under to the upper side o the piston without further compression. When the piston has reached the end of its down stroke the cylinder will be full of gas at 30 lbs.. ressure; ,and the succeedmg up stroke of tlie piston will first compress this charge of gas until it attains a pressure superior to that in the dischargel chamber G and will then discharge it throughl that chamber into the condenser, or 'what- Y ever other receiver chamber G is connected Kof lone cylinder full with. The full c linder of .gas at 3() lbs. pressure which is t us discharged is made up of gas at 15 lbs. pressure, wh1ch has entered through the lowpressure nozzle E, and about full of gas at 30 lbs. ressure,-wh ich tered from chamber taken from chamber F distance from the head as e11- B the piston must travel on its down stroke before the gas below the piston is compressed to the pressure at whlch it will lift the valvesv a against the pressure of the gas in chamber above. The distance will bey about '30% for 30 lbs.- pressure, as shown in the 4indicator card, Fig. 2. In this theoretical card 1 2 is the-'30 lbs. ressure line; 5 6 is the. 15 lbsu pressure ine; 3 4 is the 175 lbs. .pressure line. i'

The card for pressures ofthe gas above the .piston duringone reciprocation of the latter 1s' seen at 1,2, ,3, 4. vStarting at 2,'whe're th piston is at the extreme of its down stroke,

.been raised to the gas above the piston, and thereafter the sures above and below the' iston, unti the -completion of th'e down stro e of thelatter,

one third of a c linder absolute pressure 1n chamber F The amount ofgas. -solute determined by the 'is inten Astrokey of the piston. Similarly above and '.below when used to designate the cylinder spaces on each side of the piston; refer the andthe cylinder above -the piston is full of of the up strokeof the piston, represented by the line 3 4, the gas at that pressure is discharged into the condenser or other receiver i withwhich the discharge chamber G may be connected.l The moment the piston starts 'on its down stroke, the

tendency to -vacuum above the piston thus created opensl the higher pressure gas inlet valve c, and gas at 30 lbs. pressure enters the cylinder from that source, the pressure above the piston drop.- ping to 30 lbs., as indicated by line 4 1, and continuing at that pressure until the com pletion of the down stroke, as indicated by lille 1 2. f

The'card', 6, 7, 2 indicates the pressures ofthe gas below the piston during the same cycle -of movement of the latter. Starting from the point 5, the cylinder below the plston is, as the piston rises, supplied with the low pressure gas entering through inlet E at 15 lbs. pressure, so thatby the time the piston has completed its up stroke the cylinder below the .piston will be-full of gas at '15 lbs.

-pressure this being indicated by the line 5 6'. On the down stroke of the piston this charge of gas is gradually compressed, the increase of pressure vbeing indicated by the inclined line 6 7, until by the time the point 7 is reached, the pressure will have 30 lbs. pressure line of the resare equalized and are one .and the same, as indicated by line 7 2. The moment the piston again commences to rise, the tendency to vacuum thus created will open the 10W pressure inlet valve b, and the pressure in the cylinder below the piston will drop to 15 lbs., as indicated byline 2 5.` l The higher the ratio, or in other words the greater the relative difference, between the andl the abpressure at nozzle E, the greater Will be th chamber F during each cyclenof movement.

I have used herein the terms -up stroke and down-stroke of the piston merely for convenience of description, and because the e relative amount of gas .taken from com ressor cylinderhappens to be shown in the rawing 1n a position which makes such terms ap licabley. By up stroke of course is intendldd the d1scharge stroke that is to say .the stroke by which the piston discharges the com ressed gas; and by ed the return or so-called suction down stroke.

vwith mechanically operated -controlling valves can be provided in the chamber on the discharge side ofthe piston, one for each different higher pressure, connected each to its own source of gas supply and arranged to open successively during the suction stroke ,of the piston, the lower pressure first and so on up to the highest, as has before been proposed in, compressors of this general kind.

In the modification illustrated in Fig. 3, the communication between the two chambers on'opposite sides of the piston is direct, or immediate, as in Fig. 1, but the valve c'ontrolled passages, for this purpose, through the piston are dispensed with, and in lieuthereof I make use of a by-pass connection H, leading from the lower part to the upper part of the cylinder and having at its upper mouth or port an inwardly opening puppet valve h, as shown-this valve h having the same purpose and function as the valves a in the piston (Fig. 1) as lwill be understood without further explanation.

In the modificationillustrated in Fig. 4, the communication between the low pressure and high pressure chambers is not direct as in Figs. 1 and 3, but is indirect and through the lintermediary of the connections through r through the valve controlled inlet c.

which the higher pressure gas is supplied In this arrangement there is a by-pass I which at its lower end opens into the bottom of the cylinder and at its upper end discharges into the connection which feeds chamber F with the higher pressure gas. The lower endof the by-pass I is provided with an outwardly opemng puppet valve i which (like the valvesA y a in Fig.- 1) opens when the low pressure gas during the down stroke of the piston has reached a predetermined compression, and permits the thus compressed gas to pass through the by-pass l to chamber F and thence through'the suction valve c, to the discharge side of the piston. Under this arrangement in case of two or more higher back pressure inlets on the' discharge side of the piston, the by-pass Ijwould discharge into the connections supplying the highest back pressure used.

Having described my invention and the best way now known to me of carrying .the

same into practical eect, I state inconcluslon that I do not restrict myself to the strucl tural details hereinbefore shown and set forth in illustration of my invention, since manifestly the same can be widely varied without de arture from the principle of my invention, ut

What I claim herein as new and desire to secure by Letters Patent .is as follows:

1. In a gas compressor, a compressor cIylinder a reciprocatory piston therein; a va ve controlled suction port at one end of the cylinder c ommunicatmg with a source of low pressure gas; a valve controlled port at the opposite end of the cylinder for discharge of the compressed gas; a valve controlled sucfor the purposes hereinbefore set forth.

2. In a gas compressor, a compressor cylinder; a reciprocatmg piston therein; a valve controlled suction port at one end of the cylinder, communicating with ay source of lowpressure gas; a valve controlled port at the opposite end of the cylinder for discharge of the compressed gas; a valve-controlled suction port at the same end of the cylinder with the discharge port, communicating with a source of gas at higher pressure than that passage in the piston communicating with the chambers in the cylinder on opposite said communicating passage and adapted to open when the low pressure as which enters the cylinder during the disc arge stroke of the piston and is subsequently compressed during the return stroke of the latter, has, during. such return stroke, reached a predetermined de ree of compression, substanially as and or the purposes hereinbefore set orth.

In testimony whereof I affix my signature in presence of two witnesses.

y THOMAS SHIPLEY.`

Witnesses:

A. B. STRICKLER, T. A. STEBBINs.

tion'port at the same end of the cylinder with supplied through the low-pressure port; av

posite side of the piston, substantially as and sides of said piston; and a valve controlling 

